Logic built-in self-test (LBIST) is a form of built in self-test (BIST) in which hardware and/or software is built into integrated circuits allowing them to test their own operation as opposed to coupling the integrated circuits to an external testing apparatus (e.g., automated test equipment). One advantage is the ability to trigger the LBIST of an integrated circuit while running a BIST or power-on self-test (POST) of the finished product.
However, performing LBIST during a booting process (e.g., when performing POST) can alter or change the state of the boot process as LBIST testing is destructive testing. As a result, when LBIST is finished, the state of the boot process has changed which can negatively impact the functionality of the integrated circuit. As such, LBIST is a destructive test where the boot mode state of the chip under LBIST is corrupted during testing. The POST block is added to meet the ISO26262 standard.